The invention relates generally to power distribution system reliability, and more specifically to a reliability optimization workstation for use in monitoring and evaluating a power distribution system.
Reliability may be defined generally as a probability that a particular system, where a system may include a device or product, will perform satisfactorily for at least a predetermined period of time when used under a set of predetermined conditions.
Well-known examples of systems include television sets, automobiles, video cassette recorders, light bulbs, refrigerators, washing machines, personal computers, furnaces, and air conditioners. When a particularly inexpensive system, such as a light bulb, a video cassette, or a ball point pen, fails, a user of the system is likely to discard and replace it. On the other hand, when a particularly expensive system, such as an automobile, a furnace, an air conditioner, or a television set, fails, a user of the system is likely to repair, rather than discard, the system. Generally, the ultimate decision of whether to replace or repair a failed system is based on economics. More particularly, a user of the failed system is compelled to evaluate whether it is less expensive to get the device repaired or to buy a new one.
The invention provides a computer-implemented system for use in improving reliability of an electrical distribution network. To this end, the system includes a storage device configured to store different configurations of the distribution network, data corresponding to elements of the distribution network, and a set of engineering analysis modules.
In one general aspect, the system includes a processor configured to display and use a graphical user interface (GUI) to prompt a user to answer one or more questions about the distribution network. The processor is configured to receive answers from the user and retrieve data corresponding to elements of the distribution network Then, the processor automatically selects and runs one or more of the engineering analysis modules based on the received answers. Moreover, the processor automatically performs a reliability analysis of the distribution network based on the retrieved data.
Implementations may include one or more of the following features. Performing the reliability analysis may include running one or more of the engineering analysis modules.
The set of engineering analysis modules may include a reliability module that causes the processor to compute distribution network reliability indices. A power flow module may be included in the set of engineering analysis modules, the power flow module causing the processor to compute load or power flow for three-phase balanced distribution networks. The set of engineering analysis modules may also include a short circuit module that causes the processor to analyze currents and voltages in the distribution network for short circuit situations. The set of engineering analysis modules may further include a protection module that causes the processor to coordinate action of overcurrent devices in the distribution network. An unbalanced power flow module may be included in the set of engineering analysis modules, the unbalanced power flow module causing the processor to compute load or power flow for three-phase unbalanced distribution networks. The set of engineering analysis modules may include a capacitor bank placement module that causes the processor to determine size and location of capacitor banks or voltage regulators and apply economic factors. A harmonics module may also be included in the set of engineering analysis modules. The harmonics module causes the processor to calculate steady-state harmonic frequency levels throughout the distribution network.
The computer-implemented system may further include an external database associated with a utility company that supports the electrical distribution network. The processor may be configured to select and run an engineering analysis module included in the external database.
The processor may be configured to display a visual representation of the distribution network. Moreover, the visual representation may include a one-line circuit diagram. Likewise, the processor may be configured to display commands and tools that enable the user to manipulate the visual representation. The processor may be configured to display results of the reliability analysis.
In another general aspect, the computer-implemented system includes a controller configured to display a graphical user interface and receive data from a user. The user data includes an engineering analysis module selection. The controller is configured to retrieve data corresponding to elements of the distribution network, and access one or more engineering analysis modules based on the engineering analysis module selection. Based on the received user data and distribution network data, the controller computes reliability indices of the distribution network to improve distribution network reliability. Furthermore, based on the received user data and distribution network data, the controller poses hypothetical situations to the user to determine a distribution network design that improves reliability.
Implementations may include one or more of the following features. The computer-implemented system may further include an expert system that causes the controller to prompt the user to answer one or more questions about the distribution network. The expert system automatically selects and runs one or more of the engineering analysis modules based on received answers.
The set of engineering analysis modules may include a reliability module that causes the controller to compute distribution network reliability indices. The set of engineering analysis modules may also include a power flow module that causes the controller to compute load or power flow for three-phase balanced distribution networks. A short circuit module may be included in the set of engineering analysis modules. The short circuit module causes the controller to analyze current and voltages in the distribution network for short circuit situations. A protection module may also be included in the set of engineering analysis modules. The protection module causes the controller to coordinate action of overcurrent devices in the distribution network. The set of engineering analysis module may further include an unbalanced power flow module that causes the controller to compute load or power flow for three-phase unbalanced distribution networks. A capacitor bank placement module that may be included in the set of engineering analysis modules causes the controller to determine size and location of capacitor banks or voltage regulators. Lastly, a harmonics module that may be included in the set of engineering analysis modules causes the controller to calculate steady-state harmonic frequency levels throughout the distribution network.
The computer-implemented system may also include an external database associated with a utility company that supports the electrical distribution network. The controller may be configured to select and run an engineering analysis module included in the external database.
The controller may be configured to display a visual representation of the distribution network. The visual representation may include a one-line circuit diagram. The controller may be configured to display commands and tools that enable the user to manipulate the visual representation. The controller may be configured to display results of the computed reliability indices and the determined distribution network design that improves reliability.
A reliability index may include a frequency or duration of outages in the distribution network. The reliability indices may include standard indices recommended by the Institute of Electrical and Electronics Engineers (IEEE).
Other features and advantages will be apparent from the following description, including the drawings, and from the claims.